Geo Fencing is a location-based service that sends messages to smart phone users who enter a defined geographic area. Some companies send promotions to customers' smart phones when they enter a store, mall or neighborhood.
A Geo Fence can be dynamically modified as and when required in a radius around a store or point location. Or a geo-fence can be a predefined set of boundaries, like school attendance zones or neighborhood boundaries. When the location-aware device of a location-based service (LBS) user enters or exits a geo-fence, the device receives a generated notification. This notification might contain information about the location of the device. The geo fence app will send an alert on mobile or email account.